Wavy Character Research Articles

ЛАБОРАТОРНІ ДОСЛІДЖЕННЯ ДВОВИМІРНОЇ ФІЛЬТРАЦІЇ ВОДНОГО РОЗЧИНУ ТВЕРДОГО АНТИПІРОГЕНУ «PIROCOOL» ЧЕРЕЗ ВУГІЛЛЯ

Purpose. Study of filtration parameters of an aqueous solution of solid anti-pyrogen "Pirocool" and assessment of its influence on methane migration from the coal seam to the preparatory production. Method. The research was carried out on a stand for two-dimensional filtration of liquid with anti-pyrogen "Pirocool" through a coal sample. The sample is 40x40x40 mm with a hole located in the middle of the sample. Results. The obtained dependence of the relative permeability of the aqueous solution of the antipyrogen "Pirocool" on its concentration compared to the permeability of pure water. Obtained experimental data on the relative change in gas permeability of a coal sample before hydrotreatment, after hydrotreatment with water, and after repeated treatment with an aqueous solution of the anti-pyrogen "Pirocool". Scientific novelty. It consists of obtained experimental data. In addition, the wavy character of the dependence of the relative permeability of the aqueous solution of the anti-pyrogen "Pirocool" deserves attention, which may turn into a well-founded regularity in further more advanced research. Practical meaning. The obtained results prove the possibility of combining two separate safety measures in the development of coal seams - hydro loosening to prevent sudden emissions during preparatory work, and injection of aqueous solutions of anti-pyrogens in order to prevent ignition of the seam. This allows you to reduce costs and increase the productivity of mandatory preventive measures. Key words: anti-pyrogen, coal seam, liquid filtration, solution concentration, sudden emissions.

BUSCA DE PALAVRAS CHAVE EM IMAGENS DE LIVROS IMPRESSOS USANDO VISÃO COMPUTACIONAL

With the increasingly frequent use of books in digital format, people search for the desired subjects in a faster way compared to the search in physical books. This work aimed to develop a computational resource in the form of an application for Android smartphones, which, based on an image captured from a page in a book, performs searches by keywords. The purpose of using the application is to help the reader to find the desired information quickly. We use Computer Vision techniques with the aid of the OpenCV library in the development of algorithms to perform segmentation, correction of the perspective of the book page image, identification and rectification of the wavy lines, recognition and character classification. The results shown were promising with a hit rate of over 88%.

How Schrödinger’s Equation Emerges from Force Carriers

It is demonstrated how the Schrödinger equation emerges from stochastic momentum kicks of the force carriers, transmitting the fundamental interactions between the point particles. The picture is consistent with quantum field theory and points out that the force carriers are the only quantum particles. Since the latter are waves in the coordinate space, they are responsible for the wavy character of quantum mechanics.

AFM, SEM AND TEM study of damage mechanisms in cyclically strained mar-M247 at room temperature and high temperatures

Cylindrical specimens of γ́ precipitate strengthened superalloy MAR-M247 were cyclically strained under total strain control conditions using a symmetrical push–pull cycle at 23 °C, 700 °C and 800 °C in air. The fatigue hardening/softening curves and low cycle fatigue life curves are presented. Special attention is paid to the effect of temperature on plastic strain localisation and fatigue crack initiation at 23 °C, 700 °C and 800 °C. Plastic strain localisation into dislocation-rich slabs parallel to the 111slip planes was found at 23 °C and 700 °C. Plastic strain localisation manifested itself by the formation of pronounced surface relief, known as persistent slip markings (PSMs), at locations where dislocation-rich bands emerged on the surface. PSMs consisted of extrusions accompanied by parallel intrusions, where the intrusions were identified as primary crack nucleation sites at 23 °C. With an increase in the testing temperature to 700 °C, the impact of PSMs on fatigue crack initiation was reduced. At 800 °C, the appearance of both PSMs and dislocation arrangement changed significantly. The short PSMs with a wavy character appeared and bands of superlattice stacking faults (SSFs) on 111 planes with Burgers vector b of 〈112〉 type were identified. At 800 °C, fatigue cracks were initiated at the defects and carbides.

Interfacial reactions and structural properties of explosively welded titanium/copper plates

In this study, the effect of post-processing heat treatment on the interface morphology and kinetics of intermetallic phase growth in titanium/copper bimetallic sheets were analyzed using a scanning electron microscopy and mechanical testing. Ti/Cu composite was fabricated by explosive welding. Then, clads were subjected to the post-welded annealing at 973 K for times ranging between 15 min and 100h. In the as-bonded state, the interface shows a wavy character with a limited number of melted zones, which are mostly composed of phases that are not observed in the Ti-Cu equilibrium phase diagram. Short-term annealing is shown to transform non-equilibrium phases into equilibrium ones, such as TiCu4 and Ti3Cu4. For longer annealing times, the growth of four intermetallic sublayers (Ti2Cu, TiCu, Ti3Cu4, and TiCu4) distributed along the entire interface is detected. However, the growth kinetics of particular sublayers was different. Volume fraction estimation of intermetallic phases at annealing times under study revealed the largest thickness for TiCu and TiCu4 phases. The nano-hardness of intermetallic sublayers was found to drop with the Ti content.

Study of flowering patterns of Campanula L. species using computer modeling

Long-term data on flowering phenology of 9 Campanula L. species were processed using computer modeling. Modified model is proposed to describe flowering of monocarpic shoots with multi-flowered inflorescences taking into account structural inflorescence features and morphogenesis of floral zone. The flowering patterns are determined by degree of inflorescence branching and sequence of flowers opening in them. It is shown that flowering curve for simple inflorescences is unimodal: it has single peak associated with opening of terminal flower and flowers on the 1st order axes. For compound inflorescences two maxima are noted (the second of them is due to opening of flowers on the 2nd order axes), or curve has wavy character. Regression curves describing sequence of flowers opening on the 1 st order axes are different. They are C-shaped if flowering begins in lower third of the inflorescence and then spreads divergently. More often terminal flower opens first, and is accompanied by several flowers in lower third of inflorescence, while next flowers open in divergent way. In this case the regression curves are S-shaped. The proposed model reproduces picture of individual flowering with natural variability, and can be used to describe flowering of various taxa of herbaceous plants with multi-flowered inflorescences.

Macroscopic chirality of twist-bend nematic phase in bent dimers confirmed by circular dichroism

Long-range global chirality is confirmed in the twist-bend nematic phase of bent dimers using circular dichroism spectroscopy. The phase absorbs left and right circularly polarized light differently, confirming its helical rather than wavy character.

Study of the microstructure and small punch behavior of a 9Cr ODS tube

Abstract The microstructure of a 9Cr ODS tube (supplied by CEA) obtained by a powder metallurgy route followed by hot extrusion and cold pilgering of the final cladding, has been investigated by means of scanning and transmission electron microscopy. The alloy presents a weak fiber texture and a bimodal grain size distribution. Three different families of precipitates have been identified: isolated and large Ti-Al oxides, Cr rich precipitates placed preferentially at prior austenite grain boundaries and martensitic lath boundaries and a fine distribution of Y-Ti nano-oxides within grains. In order to correlate this microstructure with the mechanical properties, 3 mm diameter discs drilled from the tube wall were tested by small punch technique at room temperature, 300 °C and 500 °C to reproduce the load system to which the claddings will be subjected under service conditions. Changes in the slip character and failure mode as temperature increases were observed. At low temperatures the alloy exhibited a wavy slip character and a quasi-ductile fracture mode. At high temperature, 500 °C, the fracture tended to be more brittle, what may be attributed to an intergranular deformation mechanism leading to the weakening of grain boundaries.

ON RELIABILITY OF ASSESSMENT OF THE RAIL GAUGE STATE IN THE PLAN

For the English full text of the article please see the attached PDF-File (English version follows Russian version).ABSTRACT The data presented in the article testify to the urgent need for modernization of methods for studying horizontal geometric irregularities that provide necessary accuracy in assessment of the rail gauge state. The method for measuring the trajectory of the lateral surface of the rail head in the horizontal plane is improved. The method of converting the bending arrows from the base chord to the absolute values of the coordinates of the trajectory of the lateral surface of the rail head in the plan is modified. The influence of lateral wear of rails on traffic safety is evaluated. Particularly, the authors argue that along with the spectral methods of estimating the horizontal irregularities, it is necessary to apply the indicator of the traffic safety factor of single irregularities. According to the research the lateral undercut of the rail head in the longitudinal direction has an uneven wavy character and the results of its measurements should be used in assessing traffic safety, especially in curved sections of the track. Keywords: railway, track measuring car, horizontal irregularity, rail gauge, side wear of rails, traffic safety.

Microstructure and mechanical properties of multi-layered Al/Ti composites produced by explosive welding

Microstructure and phase in the bonding zone of explosively welded Ti/Al multilayer clads were examined by optical microscopy, scanning and transmission electron microscopy. The defect-free multilayer composite was successfully formed. The macro-scale observations showed that the interfaces between joined plates presented mixed wavy/flat shape with solidified melt inclusions located preferentially at the crest of each wave and in the wave vortex. It was found that interfaces of wavy character were always formed in layers near the explosive charge, and flattened with the increase of the distance from the top surface. The micro- scale analyses observations revealed a presence of very thin reaction layer at the flat parts of the joint plates and nano-grained structure of melted zones.

Evaluation of Rock Joint Coefficients

A computer method for evaluation of rock joint coefficients is described and several applications are presented. The method is based on two absolute numerical indicators that are formed by means of the Fourier replicas of rock joint profiles. The first indicator quantifies the vertical depth of profiles and the second indicator classifies wavy character of profiles. The absolute indicators have replaced the formerly used relative indicators that showed some artificial behavior in some cases. This contribution is focused on practical computations testing the functionality of the newly introduced indicators.

Influence of explosive welding parameters on properties of bimetal Ti-carbon steel

Explosion welding of metals is a process of great technological significance in terms of modern metal composites manufacturing possibilities Nevertheless, selecting welding parameters is not an easy task. This paper assesses the effect of various values of distance of sheets on the quality of the bond zone in titanium (Ti Gr.1) - carbon steel (P355GH) structure. The research was carried out for initial state bonds i.e. immediately following explosion welding. The results of mechanical and structural investigations were presented. In order to determine changes in the value of strengthening, microhardness tests of both the weld and the joined plates were performed. Performed metallographic analysis shows that the standoff distance affects the quality of the bond zone boundary. Smaller distance promotes the formation of waves with lower parameters (of length and height), whereas greater distances allow forming the bond of a more pronounced, repetitive wavy character, however, increasing the quantity of the fusion zone at the same time. Also, the initial distance between the materials to be joined makes for the strengthening in the areas adjacent to bond boundary. The results received allowed to conclude that for the assumed parameters it is possible to obtain Ti -carbon steel bi-metal with properties meeting the standard’s requirements.

Size effects and temperature dependence on strain-hardening mechanisms in some face centered cubic materials

The mechanical behavior of face centered cubic metals is deeply affected when specimen dimensions decrease from a few millimeters to a few micrometers. At room temperature, a critical thickness (t) to grain size (d) ratio (t/d)c was previously highlighted, under which the softening of mechanical properties became very pronounced both in terms of Hall–Petch relation and work hardening mechanisms. In this work, new experimental results are provided concerning the influence of temperature on this size effect for copper, nickel and Ni–20wt.%Cr, representative of a wide range of deformation mechanisms (i.e. dislocation slip character). It is shown that multicrystalline samples (t/d<(t/d)c) are not deeply affected by an increase in temperature, independently of the planar or wavy character of dislocation glide. For pronounced wavy slip character metals, surface effects in polycrystals (t/d>(t/d)c) are not significant enough to reduce the gap between polycrystal and multicrystal mechanical behavior when the temperature increases. However, a transition from wavy slip to planar glide mechanisms induces a modification of the polycrystalline behavior which tends toward multicrystalline one with a moderate increase in temperature. This work demonstrates that surface effects and grain size influence can be successfully disassociated for the three studied materials using an analysis supported by the Kocks–Mecking formalism. All these results are supported by microscopic investigations of dislocation substructures and compared to numerical simulations using a strain gradient plasticity model.

Heat transfer for fully developed stratified wavy gas–liquid two-phase flow in a circular cross-section receiver

Stratified gas–liquid two-phase flow occurs during the direct steam generation in the receivers. In order to understand how such a receiver can work under stratified two-phase flow regime forms, the numerical modeling of fully developed stratified wavy gas–liquid flow in a circular cross-section receiver is presented. The steady-state axial momentum and energy equation are coupled and solved together with a low Reynolds number k∼ɛ turbulence model for the eddy viscosity. The interface boundary conditions are more complex in the wavy flow than the smooth due to the unsteadiness of the wave motion itself. It is found that the interface configuration and wavy character must be taken into accounted for hydro and heat transfer simulation to be valid. Unfortunately, this has not been accounted for in all previous studies. The boundary conditions for the wave gas–liquid interface are devised from empirical consideration. In hydro dynamic simulation, the numerical calculations of global properties, such as pressure gradient and liquid holdup, shear stress distribution and the velocity field have been compared with the experimental data. In addition, for heat transfer simulation, the predictions of bulk and inside receiver wall temperature have been compared with the experimental result. It is concluded that a perfect agreement between this numerical calculation and experimental results could be achieved.

Influence of deposition conditions on electrical and mechanical properties of Sm2O3-doped CeO2 thin films prepared by EB-PVD (+IBAD) methods. Relationship between investigated film and substrate at indentation

The study of polycrystalline CeO2 + xSm2O3 (x = 0, 10.9–15.9 mol %) thin films deposited by Electron Beam Physical Vapour Deposition (EB-PVD) and Ionic Beam Assisted Deposition (IBAD) techniques on the Si substrate was devoted to the influence of deposition conditions used, namely composition x, deposition temperature Tdep and Ar+ ion bombardment as well as the structure and (micro)structure on the (micro)hardness H using the differential hardness, Hdif, as a parameter. The investigations were made using, as in our recent papers, the depth sensing indentation (DSI) technique. The study was focused on the depth dependence of the film/substrate system response on the indentation response from the surface of films up to the film/substrate interface. This study has shown that the critical indentation depth, where the influence of substrate is negligible, can be observed for some CeO2 films doped with Sm2O3 as well as for undoped CeO2 films, both deposited at Tdep = 200°C without IBAD as well as using IBAD. Besides it, a wavy character of differential curve due to the inhomogeneities of films was observed with good reproducibility at some films. It was proven, that the method of differential hardness measurement is applicable for the determination of critical indentation depth as well as for the study of microstructure response of thin films from the film surface up to the film/substrate interface. Results of this study are described and discussed.

“Diffusion waves” with the surface saturation of alloys with mobile elements

The wavy character of the distribution of alloying elements in the surface saturation zone of titanium alloys with nitrogen is established. An explanation of the causes of the appearance of ascending diffusion for alloying elements is given. A mathematical model of the process, which makes it possible to evaluate the distribution of alloying elements and the magnitude of diffusion peaks, is proposed. It is shown that the appearance of “diffusion waves” is a kinetic phenomenon, which is caused by the difference in the diffusion mobility of the saturating element and alloying elements. The relation of the magnitude of the compatibility criterion LL with the degree of varying the concentration of alloying elements in the saturation zone is established based on nitriding the titanium alloys.

Баланс азота в земледелии Балтасинского района Республики Татарстан

On the basis of 45 years data, the economic dynamics of nitrogen balance was represented, calculated in four different ways, which are defined by correspondence of accounting of credit and debit articles of nitrogen balance. When calculating the balance according to the first embodiment, we limited by comparison of economic takeaway of nitrogen, including agricultural crops (excluding biological nitrogen fixation, including symbiotic) with the receipt of it as part of mineral and organic fertilizers. In the second embodiment of nitrogen balance calculation, the economic takeaway was calculated, taking into account the symbiotic nitrogen fixation, the dimensions of which were taken equal to 2/3 of the economic removal of nitrogen by legumes. In the following two variants of calculation the authors attempted to better reflection of credit and debit articles of nitrogen balance: precipitation leaching, losses due to soil erosion, loss of gaseous nitrogen, symbiotic and non-symbiotic nitrogen fixation, nitrogen in the delivery of seeds and precipitation, according to the recommendations, which differ only by different approaches to the calculation of the size of symbiotic nitrogen fixation. Regardless of the calculation method, the fluctuations in the dynamics of nitrogen balance were about the same and had a wavy character. Nitrogen deficiency in the cycle I changed to a surplus in the next four cycles (1971-1995), but the last three cycles characterized by a negative balance again. Such dynamics of economic nitrogen balance was mainly due to changes in the flow of nitrogen in fertilizer and takeaways with crops. The highest correlation was found between the first and third embodiments of the calculation (r = 0,994), which may give a more realistic economic dynamics of the nitrogen balance.&#x0D;

The evolution of the concepts of growth, development and other related, during the last decades

The evolution of such terms as growth, differentiation, development, morphogenesis etc. is discussed. It is proposed that the term (notion) development should be understood to comprise "growth", "differentiation" and even "abscission, abortion and necrosis". The term "development" is already used in such a way by some authors. The relations among the phenomena denoted by the above terms are presented in a graphic form to show that they partly overlap. The concept that growth and development represent quantitative and qualitative aspects (respectively) of plant augmentation is criticized. The newly introduced terms "development hormone" or "development regulator" seem more suitable than "growth hormone" and "growth regulator", however, these later ones are correct and may be used. The traditional term "phytohormone" and the newly introduced one "phytoregulator" seem convenient, but it must be kept in mind that such substances may transmit information both on a chemical basis as well as on a biophysical one. An example here can be auxin; a change in the wavy character of its transport may serve as information. In some cases a complex of two or more substances may play the role of a hormone, for instance ACC and ethylene, of which one is easily transportable but little active and the other is very active but exerts its action rather locally. Other combinations of activities may exist in other such pairs.

Dielectric properties and related ferroelectric domain configurations in multiferroic BiFeO 3–BaTiO 3 solid solutions

Dielectric properties and ferroelectric domain configurations of multiferroic xBaTiO 3–(1 − x)BiFeO 3 ( x = 0.10–0.33) solid solutions synthesized by conventional solid-state reaction, were reported. A structural transition from rhombohedral to pseudo-cubic structures appeared around x = 0.33, and the formation of impurity phase of Bi 2Fe 4O 9 was effectively depressed by doping BaTiO 3. Dielectric constants of xBaTiO 3–(1 − x)BiFeO 3 solid solutions decreased with increasing the frequency, and the degree of decrease was related to the doping content of BaTiO 3. Transmission electron microscopy images revealed that the ferroelectric domain configurations in the multiferroic BiFeO 3–BaTiO 3 solid solutions with rhombohedral symmetry, exhibited a wavy character whereas a predominant intricate domain structure with fluctuating mottled contrast was observed in the multiferroic BiFeO 3–BaTiO 3 solid solution with pseudo-cubic phase structure. The presence of 1/2{1 1 1} superlattice spots in the selected area electron diffraction patterns taken from the multiferroic BiFeO 3–BaTiO 3 solid solutions with rhombohedral symmetry indicated that the ordered regions have a doubled perovskite unit cell.

Testing of explosive welding and welded joints. Wavy character of the process and joint quality

The basic defects occuring in explosive clad plates were properly systemized and the reasons of their formation were explained. Cases of cracks and delaminations in explosive clad plates were examined in this work. Various values of tensile stresses coming from loading and unloading waves were analysed, as they were the main reason of defects. The defects were connected with properties of welded materials in the joint area and beyond it. Some practical aspects of this process were shown as well.